1. Field of the Invention
The present invention relates to a member for electrophotography used in electrophotographic image-forming apparatuses such as copiers and printers and a process cartridge and an electrophotographic apparatus that include the member for electrophotography.
2. Description of the Related Art
Among electrophotographic image-forming apparatuses such as copiers and printers (hereafter, also referred to as “electrophotographic apparatus”), an electrophotographic apparatus capable of printing high-quality color images has been on the market.
Generally, a color image is formed as follows.
A toner image of each color is developed on a photosensitive member. The toner image of each color is then successively transferred onto an intermediate transfer member to form a color toner image on the intermediate transfer member. The color toner image formed on the intermediate transfer member is re-transferred onto a recording medium at a time. Thus, a recording medium on which a color toner image is formed is obtained.
In this manner, toners are brought into contact with members for electrophotography, such as a photosensitive member and an intermediate transfer member, until the toners are transferred onto a recording medium. Therefore, the surfaces of the members for electrophotography desirably have toner releasability in order to suppress melt-adhesion of toners to the members for electrophotography. Furthermore, the members for electrophotography are driven while being brought into contact with each other. Accordingly, degradation of the members for electrophotography caused by friction is desirably suppressed. Therefore, the surfaces of the members for electrophotography desirably also have resistance to friction.
Accordingly, there have been proposed methods in which the surface of a member for electrophotography is coated with a fluorine compound in order to improve toner releasability and resistance to friction. In Japanese Patent Laid-Open No. 2012-78801, a surface layer including a polymerizable fluorine resin/polymerizable siloxane-graft resin is disposed on an intermediate transfer belt in order to improve the toner releasability and resistance to friction of the surface of an intermediate transfer member. In Japanese Patent Laid-Open No. 2008-233893, the surface layer of a photosensitive member is hard-coated with a fluorine-based material and fine lubricating particles are added to the surface layer in order to improve the resistance to friction of the surface of the photosensitive member.
In these methods, the resistance to friction and toner releasability of a member for electrophotography at the initial stage of printing can be improved with certainty. However, it has been found that the toner releasability and resistance to friction of a member for electrophotography may fail to be maintained when a number of pages are printed.